Triangulum Galaxy Mosaic (M 33)

clic for 16% size 1024 x 1395 (350 kB)

clic here for 24% size 1524 x 2076 (745 kB)

clic here for 40% size 2540 x 3460 (1400 kB)

clic for 18% size 1320 x 834 (295 kB)

clic here for 36% size 2640 x 1648 (900 kB)

clic here for 60% size 4440 x 2780 (2000 kB)

About this Image

The Triangulum galaxy M 33 is another prominent member of the Local Group of galaxies. This face-on galaxy is small compared to its big apparent neighbor, the Andromeda galaxy M31, and to our Milky Way galaxy, but by this more of average size for spiral galaxies in the universe.

The distance to M 33 is approx. 3 million light years.
Many young blue stars and red H-II regions are resolved in this 9-panel mosaic.
North is left (portrait), up (landscape).

Below you find a 80% crop on NGC 604, a huge region containing ionized hydrogen, one of the largest H II regions known at all. it shows a diameter of approximately 1500 light-years and a spectrum similar to the Orion nebula M 42.

Technical Details


16" cassegrain in secondary focus at f/10 (L) and primary focus at f/3 (LHaRGB)

Mount MK-100 GEM
Camera SBIG STL-11000M at -25C, internal filter wheel
Filters Baader LRGB
Date 2005 for HaRGB, 2007-2009 for L.
Location Wildon/Austria
Sky Conditions mag 5.5 sky, 1.5-2.4" FWHM, temperature 5-10 C,
Exposure L = 120-180 min for each of the 9 panels at f/10 (20 min sub-exposures)
L:Ha:R:G:B = 120:60:80:60:80 min at f/3,
total exposure 30 h
Programs used: Maxim DL
Photoshop CS3